PicoQuant GmbH has released a data acquisition board for multichannel scaling and photon-counting applications, as well as optical time-domain reflectometry, time-of-flight mass spectrometry and rangefinding. The NanoHarp 250 is a short PCI slot card with integrated discriminators that acquires fluorescence and luminescence decays on the nano- to millisecond timescale. Time bin resolution is 4 ns, with up to 256k bins available, resulting in a usable span of 1.04 ms. The device's onboard histogram memory is 18 bits deep, and count rates of up to 50 MHz can be processed. Software-adjustable discriminators and onboard polarity switches interface the board to a variety of signal and trigger sources, such as photomultiplier tubes and single-photon avalanche photodiodes.